Surgical articulation assembly

ABSTRACT

A surgical articulation assembly is disclosed, including a control assembly and an articulable portion. The articulable portion includes at least two segments capable of independent movement. The control assembly defines an axis and three user controls configured to be engaged by an operator. Disposed within the control assembly are three pairs of diametrically opposed driving members that effects translation of a connecting member upon engagement of the user controls. An end of the connecting member is attached to one of the first and second segments of the articulable portion. As the connecting member translates with the driving members, the three user controls allow an operator to exert forces at points along the articulable portion. Also disclosed is a method of effecting articulation of a surgical articulation assembly.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. ProvisionalPatent Application No. 61/584,692, filed Jan. 9, 2012, the entiredisclosure of which is incorporated by reference herein.

BACKGROUND

1. Technical Field

The present disclosure relates generally to a surgical device for use ina minimally invasive surgical procedure. More particularly, the presentdisclosure relates to an articulating surgical assembly having at leasta first segment and a second segment that are separately movable.

2. Background of Related Art

A minimally invasive surgical procedure is one in which a surgeon entersa patient's body through one or more small opening in the patient's skinor a naturally occurring opening (e.g., mouth, anus, or vagina). Ascompared with traditional open surgeries, minimally invasive surgicalprocedures have several advantages and disadvantages. Minimally invasivesurgeries include arthroscopic, endoscopic, laparoscopic, and thoracicsurgeries. Advantages of minimally invasive surgical procedures overtraditional open surgeries include reduced trauma and recovery time forpatients.

However, some disadvantages include a lack of direct visualization ofthe surgical site and reduced dexterity of instruments, as compared totraditional open surgeries. Maneuvering surgical instruments with thenecessary degree of dexterity for surgical procedures is difficult underthese conditions, compounded by the fact that a surgeon often needs toreach off-axis points within a body cavity in the course of minimallyinvasive procedures. Accordingly, a need exists for a system capable ofarticulating surgical instrumentation through multiple planes in aninternal body cavity with accuracy and precision. It is furtherdesirable to provide a surgeon with a control system that is intuitiveand easy to operate to compensate for the lack of direct visualizationwithin a body cavity.

Accordingly, a need exists for a surgical device capable of giving asurgeon control of a surgical instrument in multiple planes of movement.

SUMMARY

A surgical articulation assembly is disclosed, including a controlassembly and an articulable portion. The surgical articulation assemblyhas a passage therethrough for receiving a surgical object. Thearticulable portion includes at least two segments capable ofindependent movement.

The control assembly defines an axis and includes an inner housing andan outer housing. The control assembly also includes three user controlsconfigured to be engaged by an operator. Each user control contains anengagement member. Disposed within the control assembly are three pairsof diametrically opposed driving members.

The driving members may be threaded, with each diametrically opposedmember having an opposing threading pattern. Disposed along a length ofeach driving member is a rotatable member having surface features forengaging the engagement members of the user controls. Diametricallyopposed driving members have a rotatable member disposed along theiraxial length to interengage the engagement member within one of thethree user controls.

Disposed on an outer surface of the driving members is a translatingmember that engages a recess of the inner housing, and translatesproximally or distally with the rotation of the driving members. Thetranslating members may have an internal thread to threadably engage thedriving members. Attached to a portion of each translating member is aportion of a connecting member. Another portion of the connecting memberis attached one of the first and second segments of the articulableportion. The connecting members may be flexible or rigid. As theconnecting member translates with the translating member axially alongthe driving members, the three user controls allow an operator to exertopposing forces at three positions along the articulable portion.

In one embodiment, the first user control effects bi-directionalarticulation of the first segment in a plane X. The first segment mayadditionally contain a series of coupling members that attach proximaland distal portions of the first segment in a manner such that theproximal and distal portions of the first segment articulate through asubstantially similar distance in opposing directions in the same plane.The second user control effects articulation of the second segment inplane X, and the third user control effects articulation of the secondsegment in a plane Y, plane Y being substantially transverse to plane X.

These and other features of the current disclosure will be explained ingreater detail in the following detailed description of the variousembodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present disclosure are described hereinbelowwith reference to the drawings, wherein:

FIG. 1 is a perspective view of a surgical articulation assembly inaccordance with the present disclosure;

FIG. 2 is a side profile view of the surgical articulation assembly asshown in FIG. 1, with a surgical object having an end effector insertedtherethrough;

FIG. 3 is a parts-separated view of the control assembly of the surgicalarticulation assembly as shown in FIG. 1;

FIG. 4 is an assembled view of a portion of the control assembly asshown in FIG. 3;

FIG. 5 is a bottom plan view of the control assembly of FIG. 4, with theparts removed;

FIG. 6 is an enlarged detail view of a portion of the actuation assemblyas shown in FIG. 4;

FIG. 7 is a parts separated view of the portion of the actuationassembly as shown in FIG. 6;

FIG. 7A is an enlarged detail view of the translating member shown inFIG. 7;

FIG. 7B is a cross-sectional view taken along the line 7B-7B of thetranslating member shown in FIG. 7A;

FIG. 7C is an enlarged detail view of the internal housing of thecontrol assembly as shown in FIG. 4;

FIG. 8 is a cross-sectional view taken along the line 8-8 of thesurgical articulation assembly of FIG. 1;

FIG. 8A is a perspective view of the articulable portion of the surgicalarticulation assembly of FIG. 1, having a first segment disposedproximally of a second segment, the second segment articulating in aplane X;

FIG. 8B is a perspective view of the articulable portion of the surgicalarticulation assembly of FIG. 8A, with the second segment articulatingin an opposing direction in plane X;

FIG. 8C is a perspective view of the articulable portion of the surgicalarticulation assembly of FIG. 1, with the first segment articulating ina plane X;

FIG. 9 is a parts separated view of the portion of the articulableportion of the surgical articulation assembly of FIG. 1;

FIG. 10 is an enlarged area of detail view of a series of movablemembers in section of the articulable portion as shown in FIG. 9;

FIG. 11 is a top plan cross-sectional view of the control assembly asshown in FIG. 1; and

FIG. 12 is an enlarged area of detail view of the control assembly asshown in FIG. 8.

Other features of the present disclosure will become apparent from thefollowing detailed description taken in conjunction with theaccompanying drawings, which illustrate, by way of example, theprinciples of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Embodiments of the presently disclosed surgical access assemblies foruse in minimally invasive surgery are described in detail with referenceto the drawings, in which like reference numerals designate identical orcorresponding elements in each of the several views. As used herein, theterm “distal” refers to that portion of the tool, or component thereofwhich is further from the user while the term “proximal” refers to thatportion of the tool or component thereof which is closer to the user.The presently disclosed surgical access assemblies are usable in anincision through a patient's tissue, in a naturally occurring orifice(e.g. mouth, anus or vagina), or through an access member.

Referring initially to FIG. 1, a surgical articulation assembly 100 isshown. Surgical articulation assembly 100 includes an articulableportion 110 extending distally from a control assembly 120. Controlassembly 120 and articulable portion 110 may be press fit, threaded,adhered, secured with a bayonet-type coupling, or utilize a securingmember such as a clamping collar. Control assembly 120 defines alongitudinal axis A1 (FIG. 8). Articulable portion 110 includes at leasta first segment 111 and a second segment 112. Second segment 112 isdisposed distally of the first segment 111. The first segment 111 andsecond segment 112 are capable of independent movement relative to thelongitudinal axis A1 and to each other, as will be discussed furtherbelow.

Turning to FIG. 2, the surgical access assembly 100 is shown in sideprofile view. Surgical articulation assembly has a passage 102 (FIG. 8)therethrough to receiving a surgical object 500 (shown in phantom view).Surgical object 500 may be an instrument capable of flexion within anarticulating member, such as graspers, forceps, probes, scalpels, orstaplers. Accordingly, surgical object 500 includes an end effector 502,shown extending through a distal end 103 of the passage 102.

Referring to FIG. 3, the control assembly 120 is shown in a partsseparated view. Control assembly includes an outer housing 121, an innerhousing 122, and three articulation assemblies 130, 140, 150 (FIG. 4).Articulation assembly 130 is disposed proximally of articulationassembly 140, which is disposed proximally of articulation assembly 150.Articulation assemblies 130, 140, 150 include components of controlassembly 120 working in cooperation to effect articulation of the firstand second segments 111, 112 of articulable portion 110 (FIG. 1), aswill be discussed further below. While first, second, and third userarticulation assemblies 130, 140, 150 are discussed below havinggenerally circular components, any suitably shaped or profiledcomponents may be used. Further, the components described below may beinterengaged and connected by a number of means not limited to thespecific structures described below.

Articulation assembly 130 includes a first user control 131, shown hereas a knob, but contemplated be any other suitable structure such as arotary dial or wheel. First user control 131 may have a textured surface132 to aid an operator in grasping the surface of user control 131.First user control 131 is configured to rotate about longitudinal axisA1 (FIG. 8). Circumferentially disposed within an inner diameter of usercontrol 131 is an anchor plate 160, which engages a proximal rim 133 ofthe user control 131. Anchor plate 160 includes apertures 161 forreceiving other components of the control assembly 120, as will bediscussed further below. Anchor plate 160 also contains a centralaperture 162 that bounds a portion of passage 102 for receiving aportion of surgical object 500 (FIG. 2). A pair of surface protrusions134 protrudes from a surface of a distal recess 135 of the first usercontrol 131. Surface protrusions 134 may be tabs as shown, or may beridges, ledges, or an otherwise textured surface.

An engagement member 136 is circumferentially disposed in the distalrecess 135 of user control 131. Engagement member 136 has a pair ofrecesses 137 that receive surface protrusions 134 such that when usercontrol 131 is rotated about longitudinal axis A1, force is transmittedto engagement member 136, which will also rotate about longitudinal axisA1. Engagement member 136 has a surface geometry 138 that will engageother components of the control assembly 120, as will be discussedfurther below. Although engagement member 136 is shown here as aplanetary gear having teeth disposed on its inner circumference, otherconfigurations are contemplated, such as a frictional wheel or leverarm.

Located distally of user control 131 is a separator plate 163. Separatorplate 163 contacts a distal surface of engagement member 136. Theinterior surface of separator plate 163 includes a series of recesses164 that contact a portion of inner housing 122, as will be discussedbelow, to inhibit separator plate 163 from rotating about thelongitudinal axis A1. Separator plate 163 and engagement member 136 areformed of materials that minimize frictional forces generated duringcontact, such as plastics, polished metals, or polymers. A lubricoustreatment may additionally be applied between separator plate 163 andengagement member 136 to minimize frictional engagement. Thus, when usercontrol 131 and engagement member 136 are rotated about longitudinalaxis A1, they encounter minimal frictional resistance from separatorplate 163.

A distal surface of separator plate 163 contacts a user control 142.User control 142 is substantially similar to user control 131, but has aproximal recess 144 in which separator plate 163 is circumferentiallydisposed. Thus, user controls 131, 142 may independently rotate aboutthe longitudinal axis A1 by virtue of the substantially stationarynature of separator plate 163 with respect to longitudinal axis A1. Asecond engagement member 136 is disposed in a distal recess 146 of usercontrol 142. A pair of tabs 145 engage recesses 137 of engagement member136 and transmit forces to the engagement member 136, causing engagementmember 136 to rotate about the longitudinal axis A1. Disposed distallyof the second engagement member 136 is a second separator plate 163.

Separator plate 163 acts to separate a third engagement member 136,which is circumferentially disposed in a proximal recess 154 of a thirduser control 152, from the second engagement member 136. Third usercontrol 152 is substantially similar to first and second user controls131, 142, and the proximal recess 154 includes tabs 156 for receivingthe third engaging member 136. The separator plates 163 maintain theindependent rotation of first, second, and third user controls 131, 142,152, and first, second, and third engagement members 136, whileminimizing the frictional forces encountered by each during rotationabout the longitudinal axis A1.

First, second, and third user controls 131, 142, 152, and associatedcomponents define a channel 123 through which inner housing 122 isdisposed. Referring for the moment to FIG. 7C, inner housing 122 is anaxial member having a plurality of recesses 124 in its outercircumference. The plurality of recesses 124 are generally indiametrically opposed pairs on inner housing 122, though other shapesand configurations are contemplated for inner housing 122. An outersurface of inner housing 122, between recesses 124, is defined by aridge 126 to engage a proximal end 129 of outer housing 121 (FIG. 3).Thus, housing 122 ensures that articulation assemblies 130, 140, 150(FIG. 4) rest proximally above outer housing 121 in a manner such thatouter housing 121 does not inhibit the rotation of the components ofarticulation assemblies 130, 140, 150 about longitudinal axis A1 (FIG.8). Inner housing 122 also includes a central aperture 127 that bounds aportion of passage 102 (FIG. 8) for receiving a surgical object 500.

Referring back to FIG. 3, the inner housing 122 is shown in relation tothe rest of the control assembly 120. Disposed within the recesses 124of the inner housing 122 are driving members 170. Driving members 170are axial members that may have surface features 179 to engageadditional components, as will be discussed below. Driving members 170are free to rotate about an axis laterally spaced from the longitudinalaxis A1. While driving members 170 are shown here having a threadedsurface, other surface configurations such as knurls, teeth, grooves, orspokes are contemplated.

Turning for the moment to the bottom plan assembly view of FIG. 5,driving members 170 and associated components are disposed indiametrically opposed pairs around inner housing 122. Diametricallyopposed pairs of driving members 170 have opposing threading patternsthat effect opposing axial forces upon rotation. Therefore, aright-handed threaded driving member 170 is diametrically opposed to aleft-handed threaded driving member 170. As will be described furtherbelow, the diametrically opposed pairs of driving members 170 cooperateto effect articulation forces on opposing surfaces of the articulableportion 110 (FIG. 1).

Referring for the moment to FIG. 7, driving members 170 may include aseparator member 173, such as a washer or spacer, disposed on a distalportion 172, proximally of a distal anchor plate 160 (FIG. 3). Separatormember 173 spaces driving members 170 from distal anchor plate 160 andhas a surface that inhibits engagement with the outer surface 179 ofdriving members 170. Thus, the separator member 173 inhibits the axialtranslation of driving members 170 through the distal anchor plate 160and maintains the driving members 170 in a substantially stationaryaxial position. A mounting cap 174 is circumferentially disposed on adistal portion 172 of driving member 170. Mounting cap 174 engagesapertures 161 (FIG. 3) of distal anchor plate 160, and has a surfaceformed of a minimally frictional material such as smooth metal, plastic,or polymer, to minimize frictional engagement with apertures 161. Amounting barrel 175 functions in a similar manner to mounting cap 174and is circumferentially disposed on a proximal portion 171 of drivingmember 170. Mounting barrel 175 engages apertures 161 of proximal anchorplate 160 and has a minimal frictional engagement with apertures 161.Thus, driving members 170 are free to rotate within control assembly 120(FIG. 3) without encountering substantial frictional forces from anchorplates 160. Alternatively, proximal and distal portions 171, 172 ofdriving members 170 may rotate within mounting barrels 175 and mountingcaps 174, respectively, with mounting barrels 175 and mounting caps 174disposed in apertures 161 by press fit, interference fit, or othersecure engagement and inhibited from rotation.

Referring to the detail view of FIG. 6, rotating members 176 arecircumferentially disposed around driving members 170, and may be fixedat a position along a length of driving members 170 with a securingmember 182, which may be a set screw as shown here, or a pin or clampingcollar. Rotating members 176 are additionally secured to driving members170 such that they do not rotate independently of driving members 170.Alternatively, rotating members 176 may be press fit or interference fitto driving members 170 to prevent the axial translation of andindependent rotation of rotating members 176 with respect to drivingmembers 170. Rotating members 176 are fixed at positions along the axiallength to align with engagement members 136 (FIG. 3). Rotating members176 have a textured outer surface 178, shown here as gear teeth, but arealso contemplated to include knurls, grooves, or ridges to interengagesurface protrusions 138 of engagement members 136 (FIG. 3). Thus, a pairof diametrically opposed driving members 170 align with first, second,or third user controls 131, 142, 152 (FIG. 3).

Circumferentially disposed around the driving members 170 aretranslating members 180. As shown here, translating members 180 may becylindrical members configured to be circumferentially disposed ondriving members 170. Other shapes and profiles are contemplated fortranslating members 180. Referring for the moment to FIG. 7A,translating members 180 each contain textured interior surfaces 182,shown here as threads, that engage surfaces 179 of driving members 170(FIG. 7). Textured surface 182 may have other configurations suitable toengage the outer surfaces of driving members 170. Protruding from a sidesurface of translating members 180 is a housing 184. Housing 184 isconfigured to engage a portion of recesses 124 of inner housing 120(FIG. 3), and translate axially with the rotation of driving members170. Housing 184 includes an aperture 186 for receiving other componentsof surgical access assembly 100 (FIG. 1), as will be discussed furtherbelow.

Turning now to the cross-sectional view of FIG. 7B, a connecting member190 is shown disposed in the housing 184 of translating member 180.Connecting member 190 may a flexible member such as a cable, as shownhere, a wire or string, or may be a rigid member such as a bar.Connecting member 190 has a tensile and/or compressive strength suitablefor articulable portion 110 (FIG. 1), as will be discussed furtherbelow. Connecting member 190 may have a proximal end 192 for engaging aportion of aperture 186 in housing 184 of translating member 180, and adistal end 194 attached to a portion of articulable portion 110.Proximal end 192 is securely fixed in housing 184 such that connectingmember 190 translates axially with translating member 180 along a lengthof driving member 170 (FIG. 7). Proximal end 192 may be compressivelytrapped by the geometry of housing 184, and may be defined by a ferrule,as shown here, may be knotted, or may be adhered to or embedded withinan interior surface of housing 184.

Referring momentarily to FIG. 4, more than one connecting member 190 maybe disposed in housing 184 (FIG. 7A). As seen in a pair of diametricallyopposed driving members 170, the presence of two or more connectingmembers 190 in a housing 184 may offer additional strength forarticulation. Alternatively, a connecting member 190 may be loopedwithin aperture 186. Also shown in FIG. 4 is the control assembly 120,fully assembled, without the outer housing 121 and user controls 131,142, 152 (FIG. 3). To aid in retaining the components of the controlassembly 120 in their relative positions, one or more securing members169 may disposed through anchor plates 160. Securing members 169 may bescrews, bolts, pins, or other suitable members, and may connect theanchor plates 160 to the inner housing 122 or extend through a lumen ininner housing 122 and connect the proximal and distal anchor plates 160.When articulation assemblies 130, 140, 150 are assembled, the securingmembers 169 will hold the respective components in compressed relationwithin the control assembly 120. Thus, the control assembly 120 may beengaged by an operator without components being forced out of alignmentduring use in a minimally invasive procedure.

The connecting members 190 extend distally through the distal anchorplate 160 (FIG. 3), and are attached to portions of the articulableportion 110 (FIG. 1), as will be discussed further below. Turning backto FIG. 3, these components are configured to be disposed above outerhousing 121, and are prevented from translating below the proximal endof outer housing 121 by the ridge 126 on the inner housing 122. Whileshown as a tapered cylindrical member, outer housing 121 is contemplatedto have a variety of shapes and profiles to accommodate components asneeded.

Disposed proximally of the proximal anchor plate 160 is a securingcollar 165. Securing collar 165 defines a channel 168 through which asurgical object 500 (FIG. 2) may be inserted. Securing collar 165includes a pair of flanges 166 that may have apertures 167 for receivinga securing member 169 (FIG. 4).

An extension tube 104 is shown extending from a distal end of housing121. Extension tube 104 bounds the passage 102 and receives a portion ofsurgical object 500 (FIG. 2). Extension tube 104 connects controlassembly 120 to the articulable portion 110 (FIG. 1). A sealing member105 may couple control assembly 120 and articulable portion 110, andminimizes the loss of fluids such as insufflation fluids through theconnection of extension tube 104 and control assembly 120. Accordingly,sealing member 105 may be a suitable material such as rubber or polymer,and may be configured as an o-ring. Extension tube 104 may be flexible.Referring momentarily back to FIG. 1, a reinforcing member 106 may braceextension tube 104 such that bending forces caused by the articulationof articulable portion 110 do not overstress extension tube 104 causingtearing or breaking. Reinforcing member 106, as shown here, may be agusset attached to extension tube 104.

Referring to FIG. 9, a portion of the articulable portion 110 is shownin parts separated view. The first and second segments 111, 112 (FIG. 1)of the articulable portion 110 may be continuous flexible members, ormay include independently movable members 114 that, when assembled,engage in a manner such that each movable member 114 is free to pivotrelative to an adjacent movable member 114. The first segment 111includes at least two sets 113 of movable members 114. A first set 113is located proximally of a second set 113, and the sets 113 areseparated by a continuous segment of articulable portion 110. The sets113 contain the same number of movable members 114 and are configured inthe substantially same manner.

Movable members 114 contain surface protrusions 115 and surface recesses116 to engage adjacent movable members 114. Movable members 114 may beconnected with connecting elements 119, which may be disposed through anaperture 117 through movable members 114. Connecting elements 119 may beflexible members such as cables or wires, or may be rigid members suchas links. As shown, sections of adjacent movable members 114 may havevarying surface protrusions 115 and surface recesses 116 such that aseries of adjacent movable members 114 is configured for articulation inone direction, and another series of adjacent movable members 114 isconfigured for articulation in a different direction. Any number andvariable configuration of alternating surface protrusions 115 in aseries of movable members 114 is contemplated to optimize articulationin multiple planes. Movable members 114 also contain a central aperture118 bounding a portion of the passage 102 and receiving a portion ofsurgical object 500 (FIG. 2).

Referring now to FIG. 10, distal ends 194 of connecting members 190 maybe disposed through apertures 117 of the distal movable member 114 of asegment 111, 112 (FIG. 1) in addition to or in place of the connectingelements 119 described above (FIG. 9). A distal end 194 of a connectingmember 190 may include a knot or ferrule, as described above withrespect to proximal end 192. Alternatively, a distal end 194 may beattached to an internal wall of a segment 111, 112 by adhesion, welding,or looping around an internal structure (not shown). Further, connectingmembers 190 may be embedded within a surface of articulable portion 110(not shown).

Turning momentarily to FIGS. 8-8C, connecting members 190 are showndiametrically opposed along movable members 114. Connecting members 190may be arranged such that two diametrically opposed pairs of connectingmembers 190 terminate in a distal portion of segment 112. As shown, thedistal ends 194 of connecting members 190 are secured arounddiametrically opposed posts 191. The connecting members 190 are loopedaround posts 191 such that forces exerted through connecting members 190are transmitted to the second segment 112 through posts 191. A pair ofdiametrically opposed connecting members 190 may additionally be loopedaround a portion of first segment 111 between the first and second sets113 of movable members 114. Additionally, a pair of coupling members 196are disposed along a central portion of articulable portion 110, suchthat segments 111 and 112 are coupled. Other arrangements arecontemplated for connecting members 190 and coupling members 196. Aswill be described further in detail below, connecting members 190cooperate such that opposing forces generated in opposing connectingmembers 190 will cause articulation of the first and second segments111, 112 articulable portion 110 through desired planes.

Referring to FIGS. 2, 8-8C, and 11-12 the operation of surgicalarticulation assembly 100 is shown. Turning initially to FIG. 2, anoperator will insert a surgical object 500 through the passage 102 (FIG.8). Where the surgical object 500 is an instrument, an end effector 502will extend through a distal end 103 of the passage 102 and into aninternal body cavity (not shown) for use in a minimally invasiveprocedure. The surgical object 500 will be disposed in the passage 102such that articulation of the articulable portion 110 will cause thesurgical object 500 to move relative to the longitudinal axis A1.Surgical object 500 and surgical articulation assembly 100 may furtherbe inserted through an access member (not shown). As seen in FIG. 11, anoperator will rotate a user control 131, 142, 152 (FIG. 3) about thelongitudinal axis A1, causing a respective engagement member 136 toengage the rotatable members 176 on a pair of diametrically opposeddriving members 170.

Turning to FIG. 12, the motion of the translating members 180 is shown.As the pair of driving members 170 having opposing surface features 179(right-handed and left-handed threads) are subject to the samerotational force applied by an engagement member 136, the rotation ofthe diametrically opposed driving members 170 will cause a translatingmember 180 to translate proximally, and an opposing translating member180 to translate distally along driving members 170. As the proximalends 192 of the connecting members 190 are securely disposed in thehousing 184 of the translating members 180, connecting members 190 willtranslate with their respective translating members 180. The attachmentof the distal ends 194 of the connecting members to a portion ofarticulable portion 110 (FIG. 10) effects a tensile or compressive forcethat results in user controlled articulation.

Referring to FIGS. 8-8C, the articulation of articulable portion 110will be described. As discussed above, a pair of diametrically opposedconnecting members 190 are looped around a portion of the first segment111 between the first and second sets 113 of movable members 114. Theopposed connecting members 190 may be looped around an internalstructure such as a hook or tab, or may be partially embedded within aportion of the first segment 111. Upon the exertion of forces throughthe opposed connecting members 190, the first segment 111 tends toarticulate in a plane X as shown. However, the presence of couplingmembers 196 ensures that the first and second sets 113 of movablemembers 114 first segment articulates through a limited range of motiondefined by the length of the coupling members 196. Additionally,substantially equally numbered sets of movable members 114 on eitherside of the looped portion of opposed connecting members 190 ensuresthat the articulation is effected substantially equally on either sideof the looped portion of opposed connecting members 190. Accordingly,first segment 111 articulates in such a manner such that proximal set113 of movable members 114 and the distal set 113 of movable members 114are disposed substantially parallel and laterally offset from each otherby virtue of the coupling members 196. In this way, an operator mayeffect articulation of first segment 111 such that the second segment112 is offset but substantially parallel to the longitudinal axis A1.Thus, an operator may engage first user control 131 to dispose theportions of the first and second segments 111, 112 along axes laterallyspaced from the longitudinal axis A1. It should be noted that whilefirst user control 131 is discussed here as effecting articulation ofthe first segment 111 in plane X, first control assembly 130 may beconfigured to effect articulation of first segment 111 through anydesired plane.

When second user control 142 (FIG. 3) is rotated about the longitudinalaxis A1, the engagement member 136, rotatable member 176, opposingdriving members 170, and translating members 180 cause a pair ofdiametrically opposed connecting members 190 attached to a portion ofthe second segment 112 to exert a force that effects articulation inplane X as shown. The diametrically opposed connecting members 190 allowfor bi-directional movement within plane X upon rotating the usercontrol 131 in a clockwise or counter-clockwise direction by exertingaxially opposing forces on opposing sides of the first segment 111.Rotation of user control 152 (FIG. 3) causes a pair of diametricallyopposed connecting members 190 terminating in the second segment 112 toarticulate second segment 112 in a plane Y that is substantiallytransverse to plane X, as shown. As plane X and plane Y aresubstantially transverse, the pair of connecting members 190 effectingarticulation in plane X and the pair of connecting members 190 effectingarticulation in plane Y are radially spaced in second segment 112. Thus,the coordination of second and third user controls 142, 152 allows anoperator to articulate second segment 112 bi-directionally in each ofplane X and transverse plane Y. It should be noted that planes X and Ymay represent any spatial planes that are substantially transverse.

Accordingly, an operator may manipulate first, second, and third usercontrols 131, 142, 152 in a manner such that the articulable portion 110is used to reach off axis points in a minimally invasive surgical site.It should be noted that the first, second, and third user controls 131,142, 152 may be associated with any arrangement of the sets ofconnecting members 190.

It will be understood that various modifications may be made to theembodiments disclosed herein. Therefore, the above description shouldnot be construed as limiting, but merely as exemplifications ofembodiments. Those skilled in the art will envision other modificationswithin the scope and spirit of the present disclosure.

What is claimed is:
 1. A surgical articulation assembly, comprising: anelongate member defining a longitudinal axis and having a passagetherethrough, a portion of the elongate member having at least a firstsegment and a second segment configured and dimensioned for movementrelative to the longitudinal axis, the second segment disposed distallyof the first segment; a first articulation assembly, the firstarticulation assembly including; a first engaging member rotatable aboutthe longitudinal axis; a first actuation apparatus operably coupled tothe first engaging member and including a first connecting memberattaching the first actuation apparatus to the first segment; and afirst user control structure mechanically engaged with the firstengaging member, the first user control structure being rotatable andcoaxially disposed about the longitudinal axis; a second articulationassembly, the second articulation assembly including; a second engagingmember rotatable about the longitudinal axis; a second actuationapparatus operably coupled to the second engaging member and including asecond connecting member attaching the second actuation apparatus to thesecond segment; and a third articulation assembly, the thirdarticulation assembly including; a third engaging member rotatable aboutthe longitudinal axis; a third actuation apparatus operably coupled tothe third engaging member and including a third connecting memberattaching the third actuation apparatus to the second segment.
 2. Thesurgical articulation assembly of claim 1, wherein a portion of theelongate member is comprised of independently movable links.
 3. Thesurgical articulation assembly of claim 1, wherein at least one of thefirst, second, or third actuation apparatuses includes a respectivefirst, second, or third connecting member terminating in a portion ofthe first or second segment.
 4. The surgical articulation assembly ofclaim 1, wherein engagement of the first, second, or third actuationapparatus transmits a force to one of the first or second segments. 5.The surgical articulation assembly of claim 4, wherein the force is acompressive force.
 6. The surgical articulation assembly of claim 4,wherein the force is a tensile force.
 7. The surgical articulationassembly of claim 1, wherein at least one of the first, second, or thirdactuation apparatuses includes a pair of connecting members disposed onopposing surfaces of the first or second segments.
 8. The surgicalarticulation assembly of claim 7, wherein forward or reverse engagementof one of the first, second, or third actuation apparatus effects forcesin opposing axial directions on respective diametrically opposedconnecting members.
 9. The surgical articulation assembly of claim 1,wherein at least one of the first, second, or third actuationapparatuses includes at least one rotatable member operably coupled to arespective engaging member.
 10. The surgical articulation assembly ofclaim 9, wherein at least a portion of the at least one rotatable memberis threaded.
 11. The surgical articulation assembly of claim 9, whereinthe at least one rotatable member rotates about an axis laterally spacedfrom the longitudinal axis.
 12. The surgical articulation assembly ofclaim 9, wherein at least one of the first, second, or third actuationapparatuses includes at least one translatable member in mechanicalcooperation with the at least one rotatable member.
 13. The surgicalarticulation assembly of claim 12, wherein the at least one translatablemember is attached to a portion of a respective connecting member. 14.The surgical articulation assembly of claim 12, wherein the at least onetranslatable member translates along a portion of the at least onerotatable member.
 15. The surgical articulation assembly of claim 1,wherein the first articulation assembly effects displacement of thefirst segment of the elongate member.
 16. The surgical articulationassembly of claim 15, wherein the first and second sets of independentlymovable members have a substantially similar configuration.
 17. Thesurgical articulation assembly of claim 16, wherein the first segmentarticulates in such a manner that the first set of independently movablemembers is disposed substantially parallel to and laterally offset fromthe second set of independently movable members.
 18. The surgicalarticulation assembly of claim 1, wherein the first segment includes afirst set of independently movable members disposed proximally of asecond set of independently movable members.
 19. The surgicalarticulation assembly of claim 1, wherein the second and thirdarticulation assemblies effect displacement of the second segment of theelongate member in substantially transverse planes.
 20. The surgicalarticulation assembly of claim 1, wherein a flexible surgical object isinsertable through the passage and is in mechanical communication with asurface of the passage.
 21. The surgical articulation assembly of claim1, wherein the second articulation assembly further includes a seconduser control structure mechanically engaged with the second engagingmember, the second user control structure being rotatable and coaxiallydisposed about the longitudinal axis of the elongate member, and thethird articulation assembly further includes a third user controlstructure mechanically engaged with the third engaging member, the thirduser control structure being rotatable and coaxially disposed about thelongitudinal axis of the elongate member.
 22. The surgical articulationassembly of claim 1, wherein the first user control structure defines athroughhole therethrough, such that the first engaging member isinsertable therethrough.
 23. The surgical articulation assembly of claim22, wherein the first user control structure includes at least oneprotrusion disposed on an inner facing surface thereof, and the firstengaging member includes at least one recess disposed on an outersurface thereof, such that the at least one protrusion of the first usercontrol structure engages the at least one recess of the first engagingmember to transfer rotational force thereto.
 24. A method of effectingarticulation of a surgical instrument, comprising: inserting at leastone surgical object through a surgical articulation assembly, thesurgical articulation assembly including; an elongate member defining alongitudinal axis and having a passage therethrough to receive the atleast one surgical object, a portion of the elongate member having atleast a first segment and a second segment configured and dimensionedfor movement relative to the longitudinal axis, the second segmentdisposed distally of the first segment; a first actuation apparatusoperably coupled to the first segment; a second actuation apparatusoperably coupled to the second segment; and a third actuation apparatusoperably coupled to the second segment; wherein at least one of thefirst, second, or third actuation apparatus includes at least onerotatable member operably coupled to the respective first, second, orthird actuation apparatus and the respective first or second segment,the at least one rotatable member rotates about an axis laterally spacedfrom the longitudinal axis; rotating a first user control structure, thefirst user control structure mechanically engaged with the firstactuation apparatus to dispose the first segment in a selectedorientation in a first plane; rotating a second user control structure,the second user control structure mechanically engaged with the secondactuation apparatus to dispose the second segment in a selectedorientation in the first plane; and rotating a third user controlstructure, the third user control structure mechanically engaged withthe third actuation apparatus to dispose the second segment in aselected orientation in a second plane, the first plane substantiallytransverse to the second plane, wherein the first, second, and thirduser control structures rotate about the longitudinal axis.
 25. Themethod of claim 24, further including inserting the surgicalarticulation assembly through an access member.
 26. The method of claim24, wherein inserting at least one surgical object includes rotating oneof the first, second, or third user control structures to effect a forcein one of the first or second segments.
 27. The method of claim 24,wherein inserting at least one surgical object includes forward orreverse engagement of one of the first, second, or third actuationapparatuses effecting articulation in opposing planar directions. 28.The method of claim 24, wherein inserting at least one surgical objectincludes the first actuation apparatus effecting displacement of thefirst segment of the elongate member.
 29. The method of claim 28,wherein rotating the first user control structure includes displacingthe first segment of the elongate member such that a proximal portion ofthe first segment is laterally spaced from the second segment of theelongate member.
 30. The method of claim 29, wherein inserting at leastone surgical object includes the proximal portion and a distal portionof the first segment of the elongate member being substantiallyparallel.
 31. The method of claim 24, wherein rotating the second andthird user control structures includes the second and third actuationapparatuses effecting displacement of the second segment of the elongatemember in substantially transverse planes.
 32. The method of claim 24,wherein inserting at least one surgical object includes inserting the atleast one surgical object through the passage such that it is directlyarticulatable.